I've had my 1988 NX650 for about a year now, and I love it. Smoother than my KLRs were and better hanling on the highway. But I've not been able to solve a problem with the engine idle. The engine always starts immediately - choke on and at fast idle. Once the engine is warmed and off choke - usually after 10 minutes or so of riding - when I come to a stop the idle drops off to nil and engine will kill. I have to blip the throttle or pull out the choke a bit to keep from stalling. Once underway, all seems ok. I've tried adjusting the idle with the Throttle Stop Screw, but that hasn't solved the problem. So, what should I try next?

I've had my 1988 NX650 for about a year now, and I love it. Smoother than my KLRs were and better hanling on the highway. But I've not been able to solve a problem with the engine idle. The engine always starts immediately - choke on and at fast idle. Once the engine is warmed and off choke - usually after 10 minutes or so of riding - when I come to a stop the idle drops off to nil and engine will kill. I have to blip the throttle or pull out the choke a bit to keep from stalling. Once underway, all seems ok. I've tried adjusting the idle with the Throttle Stop Screw, but that hasn't solved the problem. So, what should I try next?

I've had my 1988 NX650 for about a year now, and I love it. Smoother than my KLRs were and better hanling on the highway. But I've not been able to solve a problem with the engine idle. The engine always starts immediately - choke on and at fast idle. Once the engine is warmed and off choke - usually after 10 minutes or so of riding - when I come to a stop the idle drops off to nil and engine will kill. I have to blip the throttle or pull out the choke a bit to keep from stalling. Once underway, all seems ok. I've tried adjusting the idle with the Throttle Stop Screw, but that hasn't solved the problem. So, what should I try next?
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My bike has the same problem. I have found that if I keep the choke out about 1/4 of the way after the engine has warmed up, it usually wont stall when stopped.
I have been putting SeaFoam in with my gas lately, and it seems to help sometimes.

Had the same problem with sudden stalling when the hot engine running idle.
My way to fix that was to have the carb cleaned and adjusted, put the 155 main jet instead of 145 factory default, new air filter, new O-ring into the carb-to-head intake manifold, valves job done. And now I'm happy to admit that the bike runs just great for this moment, the stall problem seems to be gone.

think you'll find it's simply a result of honda's settings to keep emissions low . I had the same problem and it took nothing more than an adjustment of the pilot jet mixture screw to sort ( richened it up a bit) . some people increase the size of their pilot jet but that may not be necessary . As for the guy putting in a bigger main jet ..well can't understand how that would work as idling only involves the pilot jet.

think you'll find it's simply a result of honda's settings to keep emissions low . I had the same problem and it took nothing more than an adjustment of the pilot jet mixture screw to sort ( richened it up a bit) . some people increase the size of their pilot jet but that may not be necessary . As for the guy putting in a bigger main jet ..well can't understand how that would work as idling only involves the pilot jet.

You know, I did exactly that just yesterday, as a "maybe-this'll-help" try at fixing the problem. Turned out the pilot screw maybe an eighth of a turn - didn't want to get too drastic - and then took a 20 mile test ride. Ta Da! It didn't stall when warm! Will keep a close eye on things , but a simple 1/8th "turn-of-the-screw" seems too have helped. Thanks.

Problem is some of the US model carbs have a semi fixed pilot jet adjustment, there is only a limited range of movement unless you chop the limiters away which is part of the Mod.
When I got mine which is a Cali. model it popped and banged away on the overrun and stalled etc.
I got a carb from a German NX650 (full power) and it made it better and then when I modded it it ran sweeter again.
These bikes are setup rediculously lean from the factory for emissions, richening them makes a big difference.

I'm John from Ireland and I have recently bought a 1993 Dominator.
I have a Heap of questions.
I have been lurking through this entire tread since!

First oil burning!
I bought the dominator but it needs some tlc, the rear exhaust cans are full of leaks and holes but I have a set off eBay.
I drove it the 100kms home on the motorway/freeway but the oil dropped from half way to the very bottom of the dipstick???
I'm guessing this isn't normal? But then again a big single at high revs non stop for an hour it may.
The plan is to change the oil and filter and keep an eye on the oil level.

With oil burning you want to be very very careful of the oil levels on these RFVC engines, run it low and you could potentially wreck the head, cam and rocker arms.
Always keep it full, not even half full just full. All the time.
Don't neglect the oil changes at 2000miles either with good oil
What speed were you doing? 5000rpm or so? The engine will do it but it won't really like it.
They are great bikes, I have mine for over 10 years now.

With oil burning you want to be very very careful of the oil levels on these RFVC engines, run it low and you could potentially wreck the head, cam and rocker arms.
Always keep it full, not even half full just full. All the time.
Don't neglect the oil changes at 2000miles either with good oil
What speed were you doing? 5000rpm or so? The engine will do it but it won't really like it.
They are great bikes, I have mine for over 10 years now.

Hi Bounder!
I'm living in Kildare, I have a 1000rr and a blackbird too but I realized I'm awfull at off road so that's where the Donnie comes in!
I bought it to take part in the Paddy Dakar this year but she booked holidays on the same dates! So I have a year to set the nx650 up! And to practice.
I am a stickler for maintainence so oil changes won't be missed but I can't vouch for the previous 66,000kms?
I realized its not a motorway bike and yes I was at 120kph for nearly an hour.

This is not my first big single, I had an aprilia Pegaso 650 a few years back but only for a few months.
I got so much slagging from the mates that I sold it without even greenlaning it!
Regretted it ever since! That was comfortable too, the Nx is em a bit of a plank!

I also had a ktm 640 supermoto, great fun bike! Wheelies everywhere!

I want to get the dominator fully checked over and servied all by myself while I wait on the exhausts to arrive from Germany!
Then pop them on and hit the gravel!

What are the best nobbly Tyres bounder?
Sure throw up a pic of your Dominator!

Mine has all the fairings and tank off at the moment, I had some kind of electrical problem and stripped it to check the wiring etc.
Its a standard US model 88 with a repaint with Ford Mallard green as I couldn't match the Astro Blue honda colour.
I have a big tank for it now though 23 litre acerbis but I have to change the fairings etc to the same as yours 2nd Gen RD02.
The fairings are all gathered up but I'll need to repaint them they are all different colours! Yellow headlight surround, metallic blue fairing sides and red sidecovers, If I put it together it'll look like a Noddy bike.
Its a bit of work changing over to the later model fairings as the seat and rack are different as well.
When you say knobbies do you mean for 90% offroad and 10% on road? or something that will handle some offroad?
If you want to get in the mud then probably Pirelli MT21 are the best knobbies but for more compromise then Mitas E-09 might be better.